There had to be a better way, thought Doug Jones, facilities manager at Yarde Metals, as he stood in the sheet-metal banding area of his distribution center in Bristol, Conn.
The DC prepares aluminum, stainless steel, carbon steel and copper for shipment to customers throughout North America. Before the metal can be shipped, however, it must first go through the facility’s sheet-metal banding area, where employees use airpowered banding devices to secure cardboard to the sheet metal. Then, lift trucks pick up and transfer the bundles to the outbound shipping areas.
The sheet-metal banding operation was becoming hazardous. Pneumatic lines for banding tools were crisscrossing the floor, creating potential trip hazards. The tools, stored on the floor, were being damaged, and employees had to bend down to pick them up. Quite frequently, they had to stop working to untangle the lines and move them out of the path of oncoming lift trucks. Sometimes, they weren’t quick enough, and the lines were damaged by lift trucks. Then, employees had to stop working again to repair the lines. Productivity was down, and safety risks were up.
Jones asked Mark Capristo of Production Equipment Co. (Meriden, Conn.), a material handling equipment distributor, for help. Capristo recommended that Jones install a LodeRail enclosed track system from Columbus McKinnon (Amherst, N.Y.).
LodeRail suspended all of the pneumatic lines and banding tools over the work area. Four sets of rail were installed over the eight workstations where the sheet stock was wire strapped for shipment. Air-powered banders were suspended from two overhead bridges on each rail system. Hoses ran vertically up the stanchions of the LodeRail and horizontally across the bridges.
The rail system placed the banding tools where operators could reach them without stretching or bending. And, the potential trip hazard caused by the hoses being on the floor was eliminated. In addition, there was no longer a risk of lift trucks damaging the lines, since they were suspended and stored out of the way.
Monorail Can Mean Two
The Yarde Metals application is an example of one fastgrowing subset of the monorail market. “Found mostly in manufacturing environments, monorail systems move materials throughout a plant by means of an overhead track,” says Hal Vandiver, managing director of the Monorail Manufacturers Association (MMA, Charlotte, N.C.) and executive vice president of the Material Handling Industry of America. Vandiver says there are generally two types of monorail systems—enclosed track and patented track.
| Figure 1. With a flexible configuration of curves, switches, transfer devices and lift and drop sections, a patented track monorail can move materials throughout an entire facility without ever touching the floor. (Art courtesy: Gorbel Inc.) |
The LodeRail installed by Yarde Metals is an enclosed track monorail. Also called workstation monorails, “enclosed track is typically used for moving loads over workstations in manufacturing,” says Vandiver. Equipped for lighter loads (50 pounds to one ton), enclosed track is the best choice when ergonomics is a major factor in the purchasing decision.
When using workstation monorails, “operators only feel 1% or 2% of the force of a suspended load,” says Gene Buer, president of the crane builders group of Columbus McKinnon Corp. (Amherst, N.Y.) and executive director of the company’s branded hoist division. “For example, on a 2,000-pound load, the operator would feel like he was only moving 20 pounds.” And, it’s a well known fact that productivity and ergonomics go hand in hand; a less fatigued employee is a more productive employee.
ohn Paxton, president of Demag North America (Cleveland) and president of the MMA, says enclosed track systems are “smaller, lighter-capacity handling systems for the workstation arena.” Typical applications are low capacity but high cycling and include assembly and pick-and-place operations. Workstation monorails also support the use of manufacturing work cells, which are characteristic of efficient ergonomic manufacturing.
Enclosed track has been an increasingly popular equipment choice, as evidenced by the growth in the market. Sales have been growing 10% each year, says Paxton. “However, it won’t continue to grow at that pace,” he adds. “The total material handling industry is expected to slow down between 5% to 7% in 2008 and 2009. Even though workstation cranes were at a high already, I expect moderate growth,” he predicts. “I don’t expect the market for workstation cranes and monorails to decline.”
The other type of monorail system—patented track, also called “true” monorail—carries heavy loads over a large area of a facility. Complete with curves, switches, transfer devices and lift and drop sections, a patented track monorail “moves material on a fixed path through three dimensions in a controlled way,” says Vandiver.
The Cleveland Tramrail from Gorbel Inc. (Fishers Run, N.Y.) is a good example of a patented track monorail system. (See Figure 1.) The company describes the product as “an underhung, single-rail track installed to support hand propelled or electric motor-driven carriers.” These carriers lift and lower the load and transport it from one point to another along a fixed travel path, according to Gorbel. Materials move along custom-designed routes, and switches periodically alter the path of the load.
Higher load-carrying capacity (two tons and above) and the ability to customize for specific configurations are the distinguishing features of patented track monorails, says Jeff McNeil, marketing manager at Gorbel.
In the case of Cleveland Tramrail, McNeil says the possibilities are limited only by the physical constraints of the building. Patented track monorail systems can be configured to move materials along virtually any straight or curved path, he says. Loads can move constantly, or the system can be programmed to stop at specific workstations. An automated monorail can also be programmed to raise, lower and rotate loads; automatically store finished goods; or route specially coded products to appropriate points on an assembly line.
True monorails can move material from the rawmaterial receiving area all the way to the finished-goods area. And, monorail paths can be easily changed or expanded as a facility expands or its operations change, according to McNeil.
As with any material handling decision, it all comes down to application. “Let’s say a customer came to us with a 1,000-pound load, and they want movement to cover a small area in a rectangle. We would recommend an enclosed track system,” says McNeil. “If a customer wanted a complete solution for moving material throughout a facility, I would recommend Cleveland Tramrail.”
The two types of monorail systems, though different, share similar benefits over floor-based handling systems. “The main benefit of monorails is the ability to move material through different work cells without having to lower material to the ground,” says McNeil.
“As lean manufacturing comes to more manufacturers, they are looking at building flexibility in the system and finding more interest in monorails in place of power and free conveyor,” McNeil says. “With monorails, an operator can cue material at different paces,” McNeil explains. “And, that allows for more flexibility when the pace is not dictated.”
In addition, “overhead handling systems allow access to a much broader area,” adds Buer. “They also allow for more precise load positioning.”
That’s why Buer believes “people are looking up in the air more frequently to see if that’s an optimum solution as opposed to more traditional, floor-consuming equipment. Consideration is being given to overhead material handling—monorails in particular—instead of floor-space solutions like lift trucks or conveyors,” he says.
“The monorail industry will grow ahead of gross domestic product growth, displacing other traditional, floor-based material handling products,” Buer continues. “The market for monorails is growing faster than the traditional material handling market. Monorails take up no floor space, allowing the maximum productivity from every square foot of the facility.”
MMA to Launch Certified Program
“An engineer will review a manufacturer’s entire product line to ensure it meets national standards,” says Paxton. “In addition, the president of the company will certify that it provides spare parts, training, repair service, documentation and literature. This will differentiate high-quality manufacturers.”
A new MMA Certified Web site will also make its debut, according to Paxton. Material handling equipment users will be able to go to the Web site to view the requirements of the program and see which companies have gone through the certification process.